(revised for 5.14 gear)

Assuming a 28 inch dia. tire...
4000 RPM 64.82 MPH
3500 RPM 56.72 MPH
3000 RPM 48.62 MPH
2500 RPM 40.52 MPH
2000 RPM 32.41 MPH


Assuming a 30 inch dia. tire...
4000 RPM 69.46 MPH
3500 RPM 60.77 MPH
3000 RPM 52.09 MPH
2500 RPM 43.41 MPH
2000 RPM 34.73 MPH


Assuming a 33 inch dia. tire...
4000 RPM 76.40 MPH
3500 RPM 66.85 MPH
3000 RPM 57.30 MPH
2500 RPM 47.75 MPH
2000 RPM 38.20 MPH



Bigger diameter rear tires = faster highway speed at given rpm

Bigger diameter rear tires = more clutch slipage to get the truck moving. Not a problem though with your "granny tranny".

(I am running 33" dia. tires on my truck)

Above data calculated using this website: http://www.wallaceracing.com/gear-speed.php

Hope that helps! thumbs_up

John

Last edited by Hot Rod John; 07/04/2011 3:01 PM.
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